* {
    margin: 0;
    padding: 0;
    font-size: 0.375rem;
}

p {
    margin-left: 10px;
    text-indent: 2em;
    font-size: 100%;
}

.aa {
    margin: 20px 0;
    margin-left: 10px;
}

img {
    width: 100%;
}

#btn {
    width: 50px;
    height: 50px;
    border: 1px solid black;
    background-color: rgba(185, 185, 185);
    border-radius: 50%;
    position: fixed;
    right: 30px;
    bottom: 60px;
    opacity: 0.5;
}
#btn .fa-long-arrow-up{
    margin-left: 20px;
    line-height: 50px;
    color: #000;
}